Study On Energy And Protein Requirements Of Shaanbei White Cashmere Goat For Lactating

This study kept a foothold in the urgent need of breeding Shaanbei white cashmere goats in the fold, and Shaanbei white cashmere goats were chosen as test object. Feeding experiment and digestion and metabolism trial were combined in this study, in which two independent trials were included. Energy and protein requirements for lactating Shaanbei white cashmere goat ewes were studied preliminarily, in order to supply basic research data to establish and perfect feeding standards of Shaanbei white cashmere goat. Test1. Study on energy requirement for lactating of Shaanbei white Cashmere goatTwelve1.5year-old ewes in the second birth order which were lambing in the corresponding period were chosen to be randomly divided into three groups, and every group were fed the dietary with a CP level of131g/d and DE level of13.22,14.09and14.62MJ/d respectively; a fifty-day feeding trial(among which ten days were for preparative feeding) was conducted three days after lambing and three ewes were selected in each group to conduct the digestion and metabolism trial(collecting all the feces) of seven days after the feeding trial.The result showed that:(1) The average value of the digestibility of gross energy, metabolic rate of gross energy and metabolic rate of digestible energy of three groups were (56.14±0.72)%,(47.29±0.85)%and (84.24±0.52)%respectively, and the digestibility of gross energy, metabolic rate of gross energy and metabolic rate of digestible energy in each group were all not significantly different(P>0.05);(2) The metabolic energy required for lactating were6.3800MJ per kilogram routine milk,5.0028MJ per kilogram4%fat-corrected milk and1.7124MJ per megajoule net energy in milk, and the transformation efficiency from metabolic energy in feed to net energy in milk in lactating process was58.40%;(3) In order to improve the comparability of different studies on energy requirement for lactating, it was suggested that the energy required for producing per kilogram routine milk, per kilogram standard milk and transforming per megajoule net energy in milk were all given, and the transformation efficiency from metabolic energy in feed to net energy in milk should be estimated at the same time. Test2. Study on protein requirement for lactating of Shaanbei white Cashmere goat Twelve 1.5year-old ewes in the second birth order which were lambing in the corresponding period were chosen to be randomly divided into three groups, and every group were fed the dietary with a DE level of13.71MJ/d, and CP level of104.73,116.37and128.01g/d respectively; a fifty-day feeding trial(among which ten days were for preparative feeding) was conducted three days after lambing and three ewes were selected in each group to conduct the digestion and metabolism trial(collecting all the feces) of seven days after the feeding trial.The result showed that:(1)The average value of the apparent crude protein digestion rate was (65.10±4.68)%, and there was no significant difference in apparent crude protein digestion rate of three dietaries for lactating ewes(P>0.05);(2)The DCP required for lactating were70.85g per kilogram routine milk and1.62g per gram milk protein, and the transformation efficiency from digestible protein in feed to milk protein was61.82%;(3)In order to improve the comparability of different studies on protein requirement for lactating, it was suggested that the protein required for producing per kilogram routine milk and per gram milk protein were all given, and the transformation efficiency from digestible protein in feed to milk protein during lactating should be estimated at the same time.